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This paper is the fifth in the series of documents designed to identify the progress on the SAE Plug-in Electric Vehicle (PEV) communication task force that follows 2010-01-0837, 2011-01-0866, 2012-01-1036 and 2013-01-1475. The primary focus of this paper is to discuss the most recent revision of J2847/1 [1], which deals with Smart Charging applications, plus the initial release of J2847/3 [2], which can be thought of as dealing with “Smart Discharging” applications. Both documents are based on the use of the Smart Energy Profile 2.0 (SEP2) Application Protocol Standard (V1.0) which was completed by the ZigBee Alliance in April 2013. The standard was then accepted by the IEEE and subsequently released as IEEE 2030.5 [3]. SEP2 started with a Marketing Requirements Document (MRD) that J2836/1™ [4]expanded for the automotive Use Cases for Smart Charging, The MRD was then used to generate the SEP2 Technical Requirements Document (TRD) that set the automotive requirements in J2931/1 [5].

At the early design stage it is easier to achieve impacts on the brake noise. However most noise analyses are applied later in the development stage when the design space is limited and changes are costly. Early noise analysis is seldom applied due to lack of credible inputs for the finite element modeling, the sensitive nature of the noise, and reservations on the noise event screening of the analysis. A high quality brake finite element model of good components’ and system representation is the necessary basis for credible early noise analysis. That usually requires the inputs from existing production hardware. On the other hand in vehicle braking the frequency contents and propensity of many noise cases are sensitive to minor component design modifications, environmental factors and hardware variations in mass production. Screening the noisy modes and their sensitivity levels helps confirm the major noisy event at the early design stage.

A data processing algorithm is presented for determining the spatial orientation and position of a rigid body in impact tests based on an instrumentation scheme consisting of a triaxial angular rate sensor and a trialaxial linear accelerometer. The algorithm adopts the unit quaternion as the main parameterized representation of the spatial orientation, and calculates its time history by solving an ordinary differential equation with the angular rate sensor reading as the input. Two supplemental representations, the Euler angles and the direction cosine matrix, are also used in this work, which provide an intuitive description of the orientation, and convenience in transforming the linear accelerometer output in the instrumentation frame to the global frame. The algorithm has been implemented as a computer program, and a set of example impact tests are included to demonstrate its application.

The intake and exhaust port design plays a substantial role in performance of combustion systems. The port design determines the volumetric efficiency and in-cylinder charge motion of the spark-ignited engine which influences the thermodynamic properties directly related to the power output, emissions, fuel consumption and NVH properties. Thus intake port has to be appropriately designed to fulfill the required charge motion and high flow performance. While turbulence intensity and air-mixture quality affect dilution tolerance and fuel economy as a result, breathing ability affects wide open throttle performance. Traditional approaches require experimental techniques to reach a target balance between the charge motion and breathing capacity. Such techniques do not necessarily result in an optimized solution.

Over the past decade, the automotive industry has seen a rapid decrease in product development cycle time and an ever increasing need by original equipment manufacturers and their suppliers to differentiate themselves in the marketplace. This differentiation is increasingly accomplished by introducing new technology while continually improving the performance of existing automotive systems. In the area of automotive brake system design, and, in particular, the brake apply subsystem, an increased focus has been placed on the development of electrohydraulic apply systems and brake-by-wire systems to replace traditional pneumatic and hydraulic systems. Nevertheless, the traditional brake apply systems, especially vacuum-based or pneumatic systems, will continue to represent the majority of brake apply system production volume into the foreseeable future, which underscores the need to improve the performance and application of these traditional systems in passenger cars and light-trucks.

With increasingly stringent emissions regulations and concurrent requirements for enhanced engine thermal efficiency, a comprehensive characterization of the automotive gasoline fuel spray has become essential. The acquisition of accurate and repeatable spray data is even more critical when a combustion strategy such as gasoline direct injection is to be utilized. Without industry-wide standardization of testing procedures, large variablilities have been experienced in attempts to verify the claimed spray performance values for the Sauter mean diameter, Dv90, tip penetration and cone angle of many types of fuel sprays. A new SAE Recommended Practice document, J2715, has been developed by the SAE Gasoline Fuel Injection Standards Committee (GFISC) and is now available for the measurement and characterization of the fuel sprays from both gasoline direct injection and port fuel injection injectors.

A 2D model for vehicle-to-vehicle impact analysis that was presented in an earlier paper [1], has been used to study several two-vehicle frontal impacts with different incidence angles, frontal overlap offsets, and mass ratios. The impacts have been evaluated in terms of energy and momentum change in the bullet vehicle and the target vehicle. Based on comparisons between pre- and post-impact longitudinal, lateral, and angular components of kinetic energy, and linear and angular momenta, the impacts experienced by the target vehicle and the bullet vehicle have been classified as collinear or oblique. These results have been used to propose a definition of frontal impact based on vehicle kinematics during a crash.

A process for simultaneously optimizing the mechanical performance and minimizing the weight of an automotive body-in-white will be developed herein. The process begins with appropriate load path definition though calculation of an optimized topology. Load paths are then converted to sheet metal, and initial critical cross sections are sized and shaped based on packaging, engineering judgment, and stress and stiffness approximations. As a general direction of design, section requirements are based on an overall vehicle “design for stiffness first” philosophy. Design for impact and durability requirements, which generally call for strength rather than stiffness, are then addressed by judicious application of the most recently developed automotive grade advanced high strength steels. Sheet metal gages, including tailored blanks design, are selected via experience and topometry optimization studies.

Managing (minimizing and optimizing) the total mass of a vehicle is recognized as a critical task during the development of a new vehicle, as well as throughout its production lifecycle. This paper summarizes a literature review of, and investigation into, the strategies, methods and best practices for achieving low total mass in new vehicle programs, and/or mass reductions in existing production vehicle programs. Empirical and quantitative data and examples from the automotive manufacturers and suppliers are also provided in support of the material presented.

This paper describes the numerical results for a simplified underhood buoyancy driven flow. The simplified underhood geometry consists of an enclosure, an engine block and two exhaust cylinders mounted along the sides of the engine block. The flow condition is set up in such a way that it mimics the buoyancy driven flow condition in the underhood environment when the vehicle is parked in a windbreak with the engine shut down. The experimental measurements for temperature and velocity of the same configuration were documented in the Part I of the same title. Present study focuses on the numerical issues of calculating temperature and flow field for the same flow configuration. The predicted temperature and velocity were compared with the available measured data. The mesh sizes, mesh type and the orders of spatial and temporal accuracy of the numerical setup are discussed.

Over the past five years, the US Automotive Materials Partnership (USAMP) has brought together representatives from DaimlerChrysler, General Motors, Ford Motor Company and over 40 other participant companies from the Mg casting industry to create and test a low-cost, Mg-alloy engine that would achieve a 15 - 20 % Mg component weight savings with no compromise in performance or durability. The block, oil pan, and front cover were redesigned to take advantage of the properties of both high-pressure die cast (HPDC) and sand cast Mg creep- resistant alloys. This paper describes the alloy selection process and the casting and testing of these new Mg-variant components. This paper will also examine the lessons learned and implications of this pre-competitive technology for future applications.

A review of available information on the effect that brake rotor crossdrilling has on brake performance reveals a wide range of claims on the subject, ranging from ‘minimal effect, cosmetic only’ to substantially improving brake cooling and fade resistance. There are also several theories on why brake rotor crossdrilling could improve fade performance, including crossdrill holes providing a path for ‘de-gassing’ of the brake lining material and increasing the mechanical interaction, or ‘grip’ of the lining material on the rotor. This paper reviews three case studies in which the opportunity arose to compare the performance of brake systems with crossdrilled versus non crossdrilled brake rotors in otherwise identical brake corner designs. The effect of brake rotor crossdrilling on brake cooling, brake output, brake fade, wet brake output, and brake wear rates were studied using both on-vehicle and dynamometer data.

This paper presents a Power-Based Noise Reduction (PBNR) concept and uses PBNR to set vehicle acoustic specifications for sound package design. This paper starts with the PBNR definition and describes the correct measurement techniques. This paper also derives the asymptotic relationships among PBNR, conventional noise reduction (NR), and sound transmission loss, for a simple case consisting of the source, path, and receiver subsystems. The advantages of using PBNR over conventional Noise Reduction (NR) are finally demonstrated in vehicle measurement examples.

The complexity of vehicle-pedestrian collisions necessitates extensive validation of pedestrian computational models. While body components can be individually simulated, overall validation of human pedestrian models requires full-scale testing with post mortem human surrogates (PMHS). This paper presents the development of a full-scale pedestrian impact test plan and experimental design that will be used to perform PMHS tests to validate human pedestrian models. The test plan and experimental design is developed based on the analysis of a combination of literature review, multi-body modeling, and epidemiologic studies. The proposed system has proven effective in testing an anthropometrically correct rescue dummy in multiple instances. The success of these tests suggests the potential for success in a full-scale pedestrian impact test using a PMHS.

Since its very beginning in 1953, Corvette has been a pioneer in light weight material applications. The new 6th generation corvette high performance Z06 model required aggressive weight savings to achieve its performance and fuel economy targets. In addition to aluminum body structure and some carbon fiber components, the decision to use a magnesium front crossmember was identified to help achieve the targets. An overview of the Structural Cast Magnesium Development (SCMD) project will be presented which will provide information on key project tasks. Project focus was to develop the science and technical expertise to manufacture and validate large structural magnesium castings, which provide a weight reduction potential of 35 percent with respect to aluminum. The die cast magnesium cradle is being produced from a Mg-Al-RE alloy, designated AE44, for high temperature creep and strength performance as well as casting ductility requirements.

In recent years, the automotive industry has seen a rapid decrease in product development cycle time and a simultaneous increase in the variety of vehicles offered in the marketplace. These trends require a rigorous yet efficient systems engineering approach to the development of automotive braking systems. This paper provides an overview of an objective process for developing and predicting vehicle-level brake performance through an approach using both laboratory subsystem testing and math modeling.

This paper is intended to give a general overview of the key aerodynamic developments for the 2006 Chevrolet Corvette C6 Z06. Significant computational and wind tunnel time were used to develop the 2006 Z06 to provide it with improved high speed stability, increased cooling capability and equivalent drag compared to the 2004 Chevrolet Corvette C5 Z06.

Recently published SAE Recommended Practice J2562 - SAE Biaxial Wheel Test standardized the terminology, equipment, and test procedure for the biaxial wheel test. This test was originally presented by Fraunhofer Institut Betriebsfestigkeit - LBF (Fraunhofer Institute for Structural Durability) in SAE paper 830135 “Automotive Wheels, Method and Procedure for Optimal Design and Testing”. The first release of SAE J2562 included a generic, scalable load file applicable to wheels designed for five to eight passenger vehicles with capacity to carry a proportional amount of luggage or ballast. Future releases of SAE J2562 would include two additional load files; one applicable to light trucks that have substantial cargo capacity and one for sports cars typically limited to two passengers and marginal luggage. This report details the process used to develop the SAE Biaxial Wheel Test Load File for passenger vehicles.

Several methods are currently used to enforce motion in different types of noise and vibration models. Experimentally based FRF models often use a matrix inversion technique to enforce motion. In finite element models, the large mass method is one that is very commonly used. A literature review has shown few guidelines for determining the size of these large masses. In this paper, the relationship between the matrix inversion technique and the large mass method is derived. From this relationship, conditions necessary for these large mass FEM models to converge to the same answers as the matrix inversion technique are derived. These conditions are then used to develop a criterion for determining a smallest possible large mass. Results from a simple model are presented to demonstrate the criterion.

The following document is a set of guidelines intended to be used as a reference for the practicing automotive sound quality (SQ) engineer with the potential for application to the field of general consumer product sound quality. Practicing automotive sound quality engineers are those individuals responsible for understanding and/or conducting the physical and perceptual measurement of automotive sound. This document draws upon the experience of the four authors and thus contains many “rules-of-thumb” which the authors have found to work well in their many automotive related sound quality projects over the past years. When necessary, more detailed publications are referenced. The intent of publication of this document is to provide a reference to assist in automotive sound quality work efforts and to solicit feedback from the general sound quality community as to the completeness of the material presented.